Improvement in machines fqj twisting augers



4beneath the bed A, and tapped through a projection formed on the bottom of said slide-rest.

tait@ tatrs atent @fitta WILLARD L. ALDRlCl'l, OF NORWICH, AND VVLLAM EVANS, OF SEYMOUR, CONNECTICUT.

Letters Patent No. 67,395, dated August 6, 1867.

IMPROVEMENT IN MAHINES EOB, TWISTING AUGERS.

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T O ALL WI-IOM IT MAY OONCERN:

Be it known that we, WILLARD L. ALDRICH, of Norwich, in the county of New London, and State of Connecticut, and WILLIAM EVANS, of' Seymour, in New Haven county, State of Connecticut, have invented a Mode of Twis'ting Auger andv Bolanks; and we do hereby declare that the following is a full, clearand exact description thereof', reference being had to the accompanying drawings, making a part of this specification, in which-n Figure 1 is a side view of the twisting and finishing devices.

Figure 2 is a top view of the same.

Figure 3 shows the devices for regulating the twist.

Figure 4 is atop view showing the rollers in the act of regulating the twist ol' an auger-bit.

Similar letters of reference indicate corresponding parte in the several figures.

The object of this invention is to produce perfectly true grooves or twists in auger or bit-blanks by means of adjustable travelling-clamps or fcrmers, which are moved in a direction with the length of a blank or twisted shaft during the rotation thereo/as will be hereinafter explained` To enable others skilled in the arl: to understand our invention, we will describe its construction and operation.

ln the accompanying drawings, A represents the bed of the machine, which isv supported in a horizontal plane upon standards, and constructed with a vertical slot extending longitudinally through it, after the manner of constructing the well-known turning-lathe bed. Upon one end of this bed is the fast head-stock B, which supports the driving spindle a and its cone-pulley C; and near the opposite end of this bed A is the adjustable head-stock D, carrying the back-centre b, and the adjusting shaft to which this centre is applied. Between the fast head-stock B and the adjustable head-stock D is a sliderest or saddle, E, which is designed for supporting the devices-which impart regularity to the twist in auger or bit-blanks, after these blanks have been twisted betweenthe two parts a and b, as will be hereinafter explained. This slide-rest E should be so constructed ns tov move freely in a longitudinal direction upon the bed A, without being allowed'to have 'any lateral play. The movement is imparted to this slide-rest by means of a horizontal leading-screw, F, which is supported in bearings The screw-shal`t receives its motion from the spindle a, through the medium of suitable gearing, in a manner similar to the construction of a screw-thread cutting-lathe.` This gearing, which communicates motion from the drivingspindle to the leading-screw, should be so applied that it can be removed at pleasure and other wheels substituted, for varying the speed of the slide-rest according to the size of the bit or auger and the number of spiral turns required upon a given length of blank. Two standards G G are pivoted at their lower ends to the slide-rest E, and carry on their upper ends double convex rollers g g, which have their peripheries rounded, as shown in figs. 2 and 4, and which are arranged to rotate in diii'erent vertical planes, so as to adapt themselves to the spiral twist of an auger on both sides of it. The standards G G have oscillating nuts L h inserted in them, through which a shaft, J, passes, having rightand left-hand screw-threads cut upon it, as shown in fig. 3. Upon turning this screw-shaft, by means of a hand-wheel or crank, the rollers g g can be made to approach or recede from each other. The auger or bit-blank is constructed with that portion which is to be twisted of the proper thickness and width, and such blank is secured at its extremities by means of the clutch aon the spindle a and the back-centre ZJ. -This back-centre b is bored out to receive and centre the spur on the blank, and its end is constructed with two half-spiral abutments for receiving and holding the cutting end ofv the auger before and after the latter is twisted. The -blank being adjusted between the chuck and back-centre, the slide-rest is moved toward the adjustable head-stock to the proper point, and the rollersscrewed up tightly to the blank near the back-centre b. The female or back-centre is then given a part o f a turn, enough to twist and form the cutting ends. The blank is then twisted by turning the' spindle in the proper direction, after which the slide-rest is thrown in gear, und the rolling-clamps moved along the twisted auger, so as to regulate and render the twist perfectly uniform. l In practice provision will be made for stopping the movement of the carriage or slide-rest when the work of iinishing the blanks by the rolling-clamps is complete.

It will be seen from tbe above description 4that the, blanks are rst twisted between the chuck and backcentre, after which the rolling-clamps o r foriners are adjusted so as to run in the spiral grooves, and thus render them even and uniform.

W'e do not confine our invention to the precise construction of tb'e several parts herein described, as they may be modified as circumstances require without alfectiugthe principle of 'operation of the invention.

lVhat we claim as new, and desire te secure by Letters Patent, is-

1. Regulating the twist of angers and bits by means of the rollers g g, er their equivalents, arranged upon a slide-rest, and operating substantially as described.

2. The combina-tion of end supports a with the regulating-clamps g g, substzintially a-s described.

3. 'llie construction of the female back-centreb, substantially as described.

W. L. A'LDRICH, WILLIAM EVANS.

Witnesses:

H. B. MUNSON, FLORENCE CROWLEY. 

